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  • Photoreactive salt cocrystal: N + –H⋯N hydrogen bond and cation–π interactions support a cascade-like photodimerization of a 4-stilbazole
Title: Photoreactive salt cocrystal: N + –H⋯N hydrogen bond and cation–π interactions support a cascade-like photodimerization of a 4-stilbazole
We describe hydrogen bonds ( i.e. , N + –H⋯N) in combination with cation⋯π interactions to enable a cascade-like [2 + 2] photodimerization of 4-stilbazole in a salt cocrystal. A four-component crystal assembly is composed of photoactive pyridinium ion pair 4-stilbzH + ( 4-stilbz = trans -1-(4-pyridyl)-2-(phenyl)ethylene) and photostable molecule pair 4-stilbz . UV irradiation gives rctt -1,2-bis(4-pyridyl)-3,4-bis(phenyl)cyclobutane ( 4-pyr-ph-cb ) in quantitative yield. An intermediate structure 2 ( 4-stilbz )·( 4-pyr-ph-cb )2H + is isolated that undergoes a partial single-crystal-to-single-crystal transformation. The single-crystal X-ray data provides a snapshot of movements in the salt cocrystal in the course of the photodimerization.  more » « less
Award ID(s):
1708673
PAR ID:
10332929
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
CrystEngComm
Volume:
23
Issue:
5
ISSN:
1466-8033
Page Range / eLocation ID:
1071 to 1074
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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